In all seriousness, this study popped up in my Facebook Feed thanks to my former coach, Greg Nuckols.

The official name of the study is "A Comparison of Gluteus Maximus, Biceps Femoris, and Vastus Lateralis EMG Amplitude in the Parallel, Full, and Front Squat Variations in Resistance Trained Females". (pubmed)

When you look at the list of researchers, you'll see a couple of really well known names like Bret Contreras, aka the Glute Guy and Brad Schoenfeld, known for his hypertrophy related research. There was another study similar to this one, but it was geared for men. This closes a big gaping hole in that research and puts to rest the idea that women's muscles work any different than men's muscles.

The rest of this is simply a quote from Greg Nuckols since he puts it words better than I could:

4 major takeaways:

1) a squat is a squat is a squat. Muscle activation between all three variations (and yes, between front and back squats) is very similar. If you're just squatting to generally improve leg and hip strength, it really doesn't matter how you squat. If you squat because the squat is part of your sport (powerlifting) then squat in whatever manner allows you to lift the most weight. If you squat because the squat has really substantial carryover to your sport (weightlifting) then squat in the manner than has the most carryover.

2) can we please bury the myth you have to squat ass to grass because hamstrings co-contraction will protect your knees, but only if you bounce your ass off your ankles? Also, the myth that if your knees track forward at all, they will explode and you will die (for similar reasons - if your knees track forward, required hip extension torque will be lower, so you're hamstrings won't contract as much, so your knees will implode). Hamstrings co-contraction took place to the same degree regardless of depth (they didn't test above parallel squats, but the prior, albeit flawed, study found that the same applied to half squats as well) and regardless of bar position.

3) the squat works your glutes and quads WAY harder than it works your hamstrings. With a 10rm load, peak glute and quad activation are really high, along with average quad activation. Hamstrings? Not too much going on there. I've written quite a bit about why that's the case, and why you'd want that to be the case.

4) you can't look at muscle activation and try to extrapolate hypertrophy from it directly. Deeper squats have been shown to cause more hypertrophy, but that's not reflected (in any meaningful way) via the EMG results. Range of motion (particularly stretch, which may cause some hypertrophy signaling by itself. Also, muscles are more prone to damage in the stretched position) also plays a major role."